Electrolytic rectifier



July 1, 1930. w, HULL v 1 1,769,837

ELECTROLYTIC RECTIFIER Filed Feb. 26, 1926 Fig. 5.

Fig. 2.

Inventbf: Albert W. Hui l His Attbrne Patented July 1, 1930 UNITED STATES PATENT OFFICE ALBERT W. HULL, OF SCHENEC'IADY, NEW YORK, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK ELECTROLYTIC RECTIFIER Application filed February 26, 1926. Serial No. 90,951.

My invention relates to electrical apparawax or pitch case in a manner similar to the tus, and more particularly to electrolytic recordinary dry cell. The container is divided tifiers and similar devices which comprise into two compartments by means of a parliquid immersed electrodes. tition 2, which may be made either of porous Small rectifiers at the present time are used material such as unglazed porcelain or of to considerable extent in connection with glass. If made of the latter material, the radio apparatus and, as such apparatus is partition should fit somewhat loosely within used in the home, the rectifier should 'not give the container in order to allow for the pasofi fumes or be constructed so as to permit sage of-gas from one compartment to the the spilling of electrolyte. Furthermore, in other. The lower compartment is partly filled radio systems it "is usual to connect filter with an electrolyte 3 which may be either acid units in the output circuit of the rectifier or alkaline, as desired. Mounted in the elecin such a manner that a substantially controlyte are a cylindrical anode 4 and a surstant current may be supplied from the recrounding hollow cylindrical electrode 5 which tifier to the consumption circuit. Such units may be made of tantalum. In order to perusually comprise capacity elements and comit circulation of the electrolyte 2, the cylinoperating resistance or inductance elements. drical electrode 5 may be supported slightly It is known that large capacities, such as are out of contact with the container 1 by means required, can be obtained .by the use of elecof insulating blocks 6. Electrodes 4 and 5 trolytic condensers, containing liquid elecare connected to terminals or binding posts trolyte, and I take advantage of this fact by 7 and 8 respectively, which are mounted on incorporating these condensers in the rectithe upper end of the container'l. fier unit itself. A pair of semicylindrical tantalum plates In accordance with my invention, I have 9 and 10 surround the hollow electrode 5 and provided an air tight electrolytic cell in which are connected to the terminals 1 1 and 12, one of the electrodes comprises one of the between which a resistance or lnductance plates of a condenser which may be employed unit 13 may be connected, the latter unit being in a filter unit associated with the output mounted either on the inside or outside of the circuit of the cell. In accordance with ancell as desired. As thus constructed, the other feature of my invention, I have proinner surface'of electrode 5 acts as the cathvided means for'maintaining a low normal ode of the rectifier, while the outer surface gas pressure in a cell of the above type. thereof cooperates with plates ,9 and IQ to The novel features which I believe to be formapair of condenser units. In operation, characteristic of my invention are set forth alternating current is supplied to the cell at with particularity in the appended claims terminals 7 and 11, and a substantially con- My invention itself, however hothkasgtoMitsistant,current, duestmthe pressurefiof the "organization and method of operation, will fil ers which include the condenser units and best be understood by referencejo the fol-,flresistancenl3, is delivered at terminals 8 lowing specification taken in connection with and 12.

the'jaccompanying drawing, in which Fig. 1 During operation of the cell a large is a perspective view, partly broken away, amount of hydrogen and oxygen gas 15 11bof a half wave rectifier and a two-stage filerated at the electrodes and passes 1nto the ter; Fig. 2 is a cross section of the lower porupper compartment of the cell. In order to tion of the cell shown in Fig. 1; and Fi 3 prevent excessive pressure within the cell,

is a cross section of the lower portion 0 a provision must be made for the disposal of full wave rectifier and two-stage filter. the gases. Ordinarily, openings are made in Referring to the drawing, I have indicated the'upper part of the cell so that the gases at 1 a sealed air-tight container which may thus evolved may escape into the atmosphere be constructed of any suitable material, such and thus maintain a normal low pressure as glass, and enclosed in an air-tight sealing within the cell. The presence of such openings is undesirable, however, since they permit leakage and evaporation of the electrolyte. In the present instance the electrolytic cell is sealed air-tight and excessive gas pressure is prevented by means of a catalyzing wire 14 which is mounted in the upper compartment of the cell and connected between the carbon anode 4 and the terminal 7. The alternating current supplied to the cell heats wire 14 to a dull incandescence which will be sufiicient to cause combination of the hydrogen and oxygen and thereby prevent excessive pressure within 'the container. If desired, the wire may be coated with some especially sensitive catalyzer, such as palladium or platinum black, to in crease its efficiency. The partition 2 protects the wire 14 from splashing of the electrolyte. Since wire 14 is connected to the alternating current source it will always be heated when the rectifier is in operation.

I have indicated in Fig. 3 a modification of my invention in which both portions of the alternating current wave are. rectified. In the arrangement shown in this figure, alternating current is supplied to a transformer 15, which may be mounted in the upper compartment of the cell. A secondary winding 16 energizes a catalyzing wire 17, while another secondary winding 18 supplies current to a pair of carbon anodes 19 and 20 mounted within a hollow, cylindrical, tantalum cathode 21. The cathode 21 is provided with a partition 22 which separates the carbon anodes, and with a plurality of very small openings 23 in the base thereof to. allow for circulation of the electrolyte. A plurality of tantalum condenser plates 24 and 25 cooperate with the cathode 21 to form a pair of capacity units. A resistance or inductance element 26 cooperates with the condenser units to form a two-stage filter and thus provide a substantially constant rectified current in the output circuit of the cell. The operation of the device shown in Fig. 3 is substantially identical with that shown in Fig. 1. By the employment of both halt waves of the alternating current source, the -rectified current is maintained more nearly constant than will be the case with the half wave rectifier shown in Figs. 1 and 2.

Various modifications of my invention will readily suggest themselves to persons skilled in the art without departing from the scope of my invention as set forth in the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electrolytic cell comprising a vessel containing an electrolyte, a hollow electrode mounted in the electrolyte. a second electrode within the first mentioned electrode and a pair of metallic plates cooperating with the ating with one of said electrodes to form a condenser and thereby maintain a substantially continuous fiow of rectified current, and means mounted in said receptacle folmaintaining the gas pressure therein substantially constant when alternating current V is supplied to the rectifier unit.

4. In combination, a rectifier unit comprising an air-tight receptacle containing an electrolyte, a pair of electrodes mounted in said electrolyte, an electrical filter unit mounted in the receptacle and adapted to maintain a constant current output from the unit, and means for maintaining the gas pressure in the receptacle substantially constant when alternating current is supplied to the rectifier unit.

5. In combination, a rectifier unit comprising an air-tight container, an electrolyte therein, a pair of electrodes mounted in the electrolyte. means whereby alternating current may be supplied to said rectifier unit, and means responsive to said alternating current for maintaining the gas pressure in said cell substantially constant.

6. In combination. a rectifier unit comprising a container, an electrolyte therein, a pair of electrodes mounted in the electrolyte, means whereby an alternating current may be supplied to said rectifier unit, and means responsive to said alternating current for causing continuous chemical combination of the gaseous products of electrolysis in the unit.

In witness whereof, I have hereunto set my hand this 25th day of February, 1926.

ALBERT W. HULL. 

